This application is a National Stage of International Application No. PCT/KR2006/004623 filed Nov. 7, 2006 and claims priority Korean Patent Application No. 10-2006-0010052 filed on Feb. 2, 2006, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to the controlling of a network device, and more particularly, to a method and apparatus for controlling a device to provide a service desired by a user in a home network using universal plug and play (UPnp) and a recording medium storing a program for executing the method.
2. Description of the Related Art
Remote procedure call (RPC)-based device control methods are used to provide a service desired by a user in a home network using universal plug and play (UPnP). Devices connected to the home network are classified into control points and Controlled devices in the RPC-based device control methods. In these methods, a control point is operated to transmit a previously defined command to a Controlled device according to a service request of the user.
FIG. 1 illustrates a conventional RPC-based device control method. Referring to FIG. 1, when a device performs a user's service request, a control point 100 transmits a control command regarding a user's service from among a set of previously defined commands to a Controlled device 110 according to the user's service request. The control point 100 can be defined as a controller or a control device.
FIG. 2 illustrates another conventional RPC-based device control method. Referring to FIG. 2, when three devices sequentially perform the user's service request, a control point 200 sequentially transmits control first, second, and third control commands to a first, second, and third Controlled devices 210, 220, and 230 at a proper time. The control point 200 must monitor the operation of the first, second, and third Controlled devices 210, 220, and 230. The first Controlled device 210 performs an operation according to the first control command (1a), and transmits a first result obtained by performing the operation to the second Controlled device 220 (1b). The second Controlled device 220 performs an operation according to the second control command (2a), and transmits a second result obtained by performing the operation to the third Controlled device 230 (2b). The third Controlled device 230 performs an operation according to the third control command (3a).
FIG. 3 illustrates another conventional RPC-based device control method. Referring to FIG. 3, when a device reproduces contents stored in another device, a control point 300 transmits a contents browse request message to a fourth Controlled device 310 (1). The control point 300 receives a contents list from the fourth Controlled device 310 as contents browse result information (2) and provides the contents list to the user. If the user selects contents from the contents list, the control point 300 transmits a reproduction request message for the selected contents to a fifth Controlled device 320 (3). The fifth Controlled device 320 reproduces data of the contents received from the fourth Controlled device 310 based on information included in the reproduction request message (4 and 5).
Therefore, in the conventional RPC-based device control methods, a control point and Controlled devices are clearly classified, the control point knows information on the Controlled devices in advance, the Controlled devices are connected to a network to be controlled by the control point, and it is sure that the control point is connected to the network.
However, the Controlled devices that perform a service desired by a user in a home network cannot be connected to the home network to be controlled by the control point since the Controlled devices cannot be always powered on or be connected to the network like a mobile device. Therefore, the Controlled devices must be connected to the network and set to be controlled by the control point so that the user can require the control point to send a desired service. If the control point is not connected to the network, the user cannot require the control point to send the desired service.
Also, when a service desired by the user is provided by interacting with a plurality of Controlled devices as illustrated in FIG. 2, a control point can monitor results obtained by performing operations of the plurality of devices so that the control point can transmit control commands to each of the Controlled devices in due course as described with reference to FIG. 2.
However, it is difficult for a control point to monitor operations of the plurality of Controlled devices. In particular, when the Controlled devices are different from each other, the control point must control all the Controlled devices, and thus it is more difficult to monitor the results obtained by performing the operations of the Controlled devices. To address this problem, a plurality of control points is used to control the plurality of Controlled devices. However, it is difficult for users to use such a method.